There are various techniques in the prior art for reforming round cans into a rectilinear shape. These prior art patents include the following: U.S. Pat. Nos. 1,966,349; 2,073,174; 2,429,169; 2,895,527; 2,926,774; 3,056,447; 3,271,984; and 3,736,846.
U.S. Pat. No. 3,736,846 relates to a device for reshaping cemented containers which are supplied in an end-to-end relationship directly from a body maker. The apparatus employs corner posts which extend from a transitional entrance mandrel. Reforming shoes and rotatable reforming rolls are employed to provide the external force for reshaping. Side walls of the cans are over-distended to compensate for spring-back.
U.S. Pat. No. 3,056,447 reforms round cans by conveying cans with a grip chain over a framework of bars in cooperation with external guide bars. A pair of driven paneling rolls in combination with an anvil introduce permanent panels in the side walls.
U.S. Pat. No. 1,966,349 employs a floating mandrel on a machine for reforming flatened cans into round cans and a series of support links are mounted on the conveyor chains which travel beneath the mandrel. The support links engage a slot on the underside of the mandrel and the mandrel is thus made to "float" on a series of moveable conveyor links.
Of somewhat less relevance in U.S. Pat. No. 2,073,174 in which there is shown a device for reforming metal tape using mated reforming rolls.